src/tooltipmanager.cpp

   1 /*******************************************************************************
   2  *   Copyright (C) 2008 by Konstantin Heil <konst.heil@stud.uni-heidelberg.de> *
   3  *                                                                             *
   4  *   This program is free software; you can redistribute it and/or modify      *
   5  *   it under the terms of the GNU General Public License as published by      *
   6  *   the Free Software Foundation; either version 2 of the License, or         *
   7  *   (at your option) any later version.                                       *
   8  *                                                                             *
   9  *   This program is distributed in the hope that it will be useful,           *
  10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of            *
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the             *
  12  *   GNU General Public License for more details.                              *
  13  *                                                                             *
  14  *   You should have received a copy of the GNU General Public License         *
  15  *   along with this program; if not, write to the                             *
  16  *   Free Software Foundation, Inc.,                                           *
  17  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA                *
  18  *******************************************************************************/
  19
  20 #include "tooltipmanager.h"
  21
  22 #include "dolphintooltip.h"
  23 #include "dolphinmodel.h"
  24 #include "dolphinsortfilterproxymodel.h"
  25
  26 #include <kicon.h>
  27 #include <ktooltip.h>
  28 #include <kio/previewjob.h>
  29
  30 #include <QApplication>
  31 #include <QDesktopWidget>
  32 #include <QTimer>
  33 #include <QToolTip>
  34
  35 const int PREVIEW_WIDTH = 256;
  36 const int PREVIEW_HEIGHT = 256;
  37 const int ICON_WIDTH = 128;
  38 const int ICON_HEIGHT = 128;
  39 const int PREVIEW_DELAY = 250;
  40
  41 K_GLOBAL_STATIC(DolphinBalloonTooltipDelegate, g_delegate)
  42
  43 ToolTipManager::ToolTipManager(QAbstractItemView* parent,
  44                                DolphinSortFilterProxyModel* model) :
  45     QObject(parent),
  46     m_view(parent),
  47     m_dolphinModel(0),
  48     m_proxyModel(model),
  49     m_timer(0),
  50     m_previewTimer(0),
  51     m_waitOnPreviewTimer(0),
  52     m_item(),
  53     m_itemRect(),
  54     m_preview(false),
  55     m_generatingPreview(false),
  56     m_previewIsLate(false),
  57     m_previewPass(0),
  58     m_emptyRenderedKToolTipItem(0),
  59     m_pix()
  60 {
  61     KToolTip::setToolTipDelegate(g_delegate);
  62
  63     m_dolphinModel = static_cast<DolphinModel*>(m_proxyModel->sourceModel());
  64     connect(parent, SIGNAL(entered(const QModelIndex&)),
  65             this, SLOT(requestToolTip(const QModelIndex&)));
  66     connect(parent, SIGNAL(viewportEntered()),
  67             this, SLOT(hideToolTip()));
  68
  69     m_timer = new QTimer(this);
  70     m_timer->setSingleShot(true);
  71     connect(m_timer, SIGNAL(timeout()),
  72             this, SLOT(prepareToolTip()));
  73
  74     m_previewTimer = new QTimer(this);
  75     m_previewTimer->setSingleShot(true);
  76     connect(m_previewTimer, SIGNAL(timeout()),
  77             this, SLOT(startPreviewJob()));
  78
  79     m_waitOnPreviewTimer = new QTimer(this);
  80     m_waitOnPreviewTimer->setSingleShot(true);
  81     connect(m_waitOnPreviewTimer, SIGNAL(timeout()),
  82             this, SLOT(prepareToolTip()));
  83
  84     m_view->viewport()->installEventFilter(this);
  85 }
  86
  87 ToolTipManager::~ToolTipManager()
  88 {
  89 }
  90
  91 void ToolTipManager::hideTip()
  92 {
  93     hideToolTip();
  94 }
  95
  96 bool ToolTipManager::eventFilter(QObject* watched, QEvent* event)
  97 {
  98     if ((watched == m_view->viewport()) && (event->type() == QEvent::Leave)) {
  99         hideToolTip();
 100     }
 101
 102     return QObject::eventFilter(watched, event);
 103 }
 104
 105 void ToolTipManager::requestToolTip(const QModelIndex& index)
 106 {
 107     if (index.column() == DolphinModel::Name) {
 108         m_waitOnPreviewTimer->stop();
 109         KToolTip::hideTip();
 110
 111         m_itemRect = m_view->visualRect(index);
 112         const QPoint pos = m_view->viewport()->mapToGlobal(m_itemRect.topLeft());
 113         m_itemRect.moveTo(pos);
 114
 115         const QModelIndex dirIndex = m_proxyModel->mapToSource(index);
 116         m_item = m_dolphinModel->itemForIndex(dirIndex);
 117
 118         // Only start the previewJob when the mouse has been over this item for 200msec,
 119         // this prevents a lot of useless previewJobs (when passing rapidly over a lot of items).
 120         m_previewTimer->start(200);
 121         // reset these variables
 122         m_preview = false;
 123         m_previewIsLate = false;
 124         m_previewPass = 0;
 125
 126         m_timer->start(500);
 127     } else {
 128         hideToolTip();
 129     }
 130 }
 131
 132 void ToolTipManager::hideToolTip()
 133 {
 134     m_timer->stop();
 135     m_previewTimer->stop();
 136     m_waitOnPreviewTimer->stop();
 137     m_previewIsLate = false;
 138     KToolTip::hideTip();
 139 }
 140
 141 void ToolTipManager::prepareToolTip()
 142 {
 143     if (m_generatingPreview) {
 144         if (m_previewPass == 1) {
 145             // We waited 250msec and the preview is still not finished,
 146             // so show the toolTip with a transparent image of maximal width.
 147             // When the preview finishes, m_previewIsLate will cause
 148             // a direct update of the tooltip, via m_emptyRenderedKToolTipItem.
 149             QPixmap paddedImage(QSize(PREVIEW_WIDTH, 32));
 150             m_previewIsLate = true;
 151             paddedImage.fill(Qt::transparent);
 152             KToolTipItem* toolTip = new KToolTipItem(paddedImage, m_item.getToolTipText());
 153             m_emptyRenderedKToolTipItem = toolTip; // make toolTip accessible everywhere
 154             showToolTip(toolTip);
 155         }
 156
 157         ++m_previewPass;
 158         m_waitOnPreviewTimer->start(250);
 159     } else {
 160         // The preview generation has finished, find out under which circumstances.
 161         if (m_preview && m_previewIsLate) {
 162             // We got a preview, but it is late, the tooltip has already been shown.
 163             // So update the tooltip directly.
 164             m_emptyRenderedKToolTipItem->setData(Qt::DecorationRole, KIcon(m_pix));
 165             return;
 166         }
 167
 168         KIcon icon;
 169         if (m_preview) {
 170             // We got a preview.
 171             icon = KIcon(m_pix);
 172         } else {
 173             // No preview, so use an icon.
 174             // Force a 128x128 icon, a 256x256 one is far too big.
 175             icon = KIcon(KIcon(m_item.iconName()).pixmap(ICON_WIDTH, ICON_HEIGHT));
 176         }
 177
 178         KToolTipItem* toolTip = new KToolTipItem(icon, m_item.getToolTipText());
 179         showToolTip(toolTip);
 180     }
 181 }
 182
 183 void ToolTipManager::showToolTip(KToolTipItem* tip)
 184 {
 185     if (QApplication::mouseButtons() & Qt::LeftButton) {
 186         delete tip;
 187         tip = 0;
 188         return;
 189     }
 190
 191     KStyleOptionToolTip option;
 192     // TODO: get option content from KToolTip or add KToolTip::sizeHint() method
 193     option.direction      = QApplication::layoutDirection();
 194     option.fontMetrics    = QFontMetrics(QToolTip::font());
 195     option.activeCorner   = KStyleOptionToolTip::TopLeftCorner;
 196     option.palette        = QToolTip::palette();
 197     option.font           = QToolTip::font();
 198     option.rect           = QRect();
 199     option.state          = QStyle::State_None;
 200     option.decorationSize = QSize(32, 32);
 201
 202     QSize size;
 203     if (m_previewIsLate) {
 204         QPixmap paddedImage(QSize(PREVIEW_WIDTH, PREVIEW_HEIGHT));
 205         KToolTipItem* maxiTip = new KToolTipItem(paddedImage, m_item.getToolTipText());
 206         size = g_delegate->sizeHint(&option, maxiTip);
 207         delete maxiTip;
 208         maxiTip = 0;
 209     }
 210     else {
 211         size = g_delegate->sizeHint(&option, tip);
 212     }
 213     const QRect desktop = QApplication::desktop()->screenGeometry(m_itemRect.bottomRight());
 214
 215     // m_itemRect defines the area of the item, where the tooltip should be
 216     // shown. Per default the tooltip is shown in the bottom right corner.
 217     // If the tooltip content exceeds the desktop borders, it must be assured that:
 218     // - the content is fully visible
 219     // - the content is not drawn inside m_itemRect
 220     const bool hasRoomToLeft  = (m_itemRect.left()   - size.width()  >= desktop.left());
 221     const bool hasRoomToRight = (m_itemRect.right()  + size.width()  <= desktop.right());
 222     const bool hasRoomAbove   = (m_itemRect.top()    - size.height() >= desktop.top());
 223     const bool hasRoomBelow   = (m_itemRect.bottom() + size.height() <= desktop.bottom());
 224     if (!hasRoomAbove && !hasRoomBelow && !hasRoomToLeft && !hasRoomToRight) {
 225         delete tip;
 226         tip = 0;
 227         return;
 228     }
 229
 230     int x = 0;
 231     int y = 0;
 232     if (hasRoomBelow || hasRoomAbove) {
 233         x = QCursor::pos().x() + 16; // TODO: use mouse pointer width instead of the magic value of 16
 234         if (x + size.width() >= desktop.right()) {
 235             x = desktop.right() - size.width();
 236         }
 237         y = hasRoomBelow ? m_itemRect.bottom() : m_itemRect.top() - size.height();
 238     } else {
 239         Q_ASSERT(hasRoomToLeft || hasRoomToRight);
 240         x = hasRoomToRight ? m_itemRect.right() : m_itemRect.left() - size.width();
 241
 242         // Put the tooltip at the bottom of the screen. The x-coordinate has already
 243         // been adjusted, so that no overlapping with m_itemRect occurs.
 244         y = desktop.bottom() - size.height();
 245     }
 246
 247     KToolTip::showTip(QPoint(x, y), tip);
 248 }
 249
 250
 251
 252 void ToolTipManager::startPreviewJob()
 253 {
 254     m_generatingPreview = true;
 255     KIO::PreviewJob* job = KIO::filePreview(KUrl::List() << m_item.url(),
 256                                             PREVIEW_WIDTH,
 257                                             PREVIEW_HEIGHT);
 258     job->setIgnoreMaximumSize(true);
 259
 260     connect(job, SIGNAL(gotPreview(const KFileItem&, const QPixmap&)),
 261             this, SLOT(setPreviewPix(const KFileItem&, const QPixmap&)));
 262     connect(job, SIGNAL(failed(const KFileItem&)),
 263             this, SLOT(previewFailed(const KFileItem&)));
 264 }
 265
 266
 267 void ToolTipManager::setPreviewPix(const KFileItem& item,
 268                                    const QPixmap& pixmap)
 269 {
 270     if (m_item.url() != item.url()) {
 271         m_generatingPreview = false;
 272         return;
 273     }
 274
 275     if (m_previewIsLate) {
 276         // always use the maximal width
 277         QPixmap paddedImage(QSize(PREVIEW_WIDTH, pixmap.height()));
 278         paddedImage.fill(Qt::transparent);
 279         QPainter painter(&paddedImage);
 280         painter.drawPixmap((PREVIEW_WIDTH - pixmap.width()) / 2, 0, pixmap);
 281         m_pix = paddedImage;
 282     } else {
 283         m_pix = pixmap;
 284     }
 285     m_preview = true;
 286     m_generatingPreview = false;
 287 }
 288
 289 void ToolTipManager::previewFailed(const KFileItem& item)
 290 {
 291     Q_UNUSED(item);
 292     m_generatingPreview = false;
 293 }
 294
 295 #include "tooltipmanager.moc"